Advising individuals with allergies on their suitability for COVID-19 Vaccine AstraZeneca

Eimear Maguire, Senior Medicines Information Pharmacist, North West Medicines Information CentrePublished Last updated See all updates

Advice on whether people with a previous allergic reaction can have the COVID-19 Vaccine AstraZeneca.

Background

Individuals due to be vaccinated may have had previous allergies, and may ask their healthcare professional for advice on their suitability for vaccination.

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that:

  • those with allergies, including anaphylaxis, to a food, insect sting or most medicines (where the trigger has been identified), can proceed with vaccination as normal according to local guidelines, as long as they are not known to be allergic to any component (excipient) of the vaccine;
  • anyone with a family history of allergies, a previous non-systemic reaction to a vaccine, hypersensitivity to non-steroidal anti-inflammatory drugs (e.g. aspirin, ibuprofen) or mastocytosis can proceed with vaccination as normal, according to local guidelines.

Below is a summary of knowledge about suitability for vaccination based on previous allergy status.

First dose of COVID-19 vaccine allergy

Allergy to a previous dose of AstraZeneca COVID-19 vaccine or other medicines may affect suitability for vaccination. Public Health England’s Immunisation Against Infectious Disease (the Green book) states that:

  • Individuals with a prior history of systemic allergic reaction (including immediate-onset anaphylaxis) to a previous dose or any component of the AstraZeneca vaccine should not receive it.

Seek advice from an allergy specialist regarding the above patients.

Our decision tool below will guide you through treating patients with prior allergy.

COVID-19 Vaccine Prior Allergy Decision Tool

Advice end-points

Given the nature of the previous reaction, you should seek advice from a specialist before proceeding.

The patient can have the second dose using the same vaccination in any vaccination setting.

Observe the patient for 30 minutes after they’ve received the vaccine.

The patient can have the second dose using the same vaccination in any vaccination setting.

Consider pre-treatment with a non-sedating oral antihistamine 30 minutes beforehand.

Excipients

The Information for Healthcare Professionals states that a hypersensitivity to any of the excipients is a contraindication to the vaccine use.

Excipients present

The excipients listed in the manufacturer’s information are as follows:

  • L-Histidine
  • L-Histidine hydrochloride monohydrate
  • Magnesium chloride hexahydrate
  • Polysorbate 80
  • Ethanol
  • Sucrose
  • Sodium chloride
  • Disodium edetate dihydrate
  • Water for injections

Polysorbate 80 allergy

The AstraZeneca COVID-19 vaccine contains polysorbate 80, according to the Information for Healthcare Professionals. Individuals with an allergy to polysorbate 80 should not receive the vaccine, and should be discussed with an allergist.

Polyethylene glycol (PEG) allergy

PEG is not present in the AstraZeneca COVID-19 vaccine, according to the Information for Healthcare Professionals; however, it does contain polysorbate 80. Public Health England’s Immunisation Against Infectious Disease (the Green Book) advises that some people with PEG allergy may also be allergic to polysorbate 80 which is widely used in medicines and foods. Some injected influenza vaccines (including the main vaccine used in over 65 year olds) contain polysorbate 80. Individuals who have tolerated polysorbate 80 containing injections are likely to tolerate the AstraZeneca vaccine.

Therefore, unless otherwise contraindicated, The Green Book  advises that the AstraZeneca COVID-19 vaccine may be used as an alternative in people with a PEG allergy, or a suspected PEG allergy, particularly if they previously tolerated an injected influenza vaccine. However, all such patients should be discussed with an allergist prior to vaccination.  If vaccination proceeds following discussion with the allergy specialist, it should be administered in a setting with full resuscitation facilities (e.g. a hospital), and a 30 minute observation period is recommended; some patients may benefit from pre-treatment with antihistamine – however, be aware that this may mask initial symptoms of a reaction. (See also the “Medicines allergy” section below).

Public Health England’s Immunisation Against Infectious Disease (the Green Book) also states that it is unclear whether PEG is the only cause of allergic reactions in patients with systemic allergic symptoms after the first dose of the Pfizer-BioNTech vaccine.

Medicines allergy

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that individuals with previous allergy to a medicine (where the trigger has been identified), including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine. People with hypersensitivity to nonsteroidal anti-inflammatory drugs e.g. aspirin or ibuprofen, can also receive the AstraZeneca COVID-19 vaccine. However, the Green Book also states that the following individuals should be discussed with an allergy specialist, prior to vaccination (this may indicate PEG allergy; see also “PEG allergy” section above):

  • Those with a history of immediate onset-anaphylaxis to multiple classes of drugs with the trigger unidentified.
  • Those with a history of anaphylaxis to a vaccine, an injected antibody preparation or a medicine likely to contain PEG (e.g. depot steroid injection, laxative).

See also the UK Chemotherapy board Clinician Frequently Asked Questions (FAQs) and guidance on COVID-19 vaccine for patients receiving Systemic Anti-Cancer Therapy (February 2021).  This has been produced in response to questions about use of COVID-19 vaccines in patients who have experienced a reaction to systemic anti-cancer therapy (SACT) or excipients of SACT.

Antibiotics

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that individuals with previous allergy to a medicine (where the trigger has been identified), including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine.

“Sulfa” medicines

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that individuals with previous allergy to a medicine (where the trigger has been identified), including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine.

The Information for Healthcare Professionals does not indicate that any “sulfa” medicines are present in the AstraZeneca COVID-19 vaccine.

Other allergy considerations

As well as allergy considerations associated with previous vaccination and to excipients, other considerations are as follows.

Foods

Previous allergy to foods is covered in Public Health England’s Immunisation Against Infectious Disease (the Green book) which states that individuals with previous allergy to food, including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine.

The manufacturer states that AstraZeneca COVID-19 vaccine does not contain:

  • Egg
  • Gelatin
  • Gluten
  • Peanut or tree nut derivatives
  • Soy

However, AstraZeneca does not manufacture the raw materials used in its products, and the suppliers may periodically change. Lack of contact with other ingredients during the manufacturing process, such as the ones listed above, cannot be guaranteed.

Latex

Our view is that the risks associated with previous latex allergy are low. The vaccine can be considered not to contain latex and poses the same minimal risk as other injectable medicines presented in vials with a halobutyl rubber stopper.

This view is formed from:

However, even if the components of an injection do not contain latex, or latex is not used as a raw material during manufacturing, most manufacturers of injectable products advise they cannot guarantee minute amounts of latex are not contained in raw materials obtained from their suppliers or the product has not come into contact with latex during the manufacturing process.

Patients with an allergy to latex can be directed to the Anaphylaxis Campaign website for information.

Thiomersal content

The manufacturer states that this vaccine does not contain any preservatives, thiomersal or any mercury derived product.

Summary of allergy considerations

The table below is a pictorial summary of the management of patients with a history of allergy, reproduced with kind permission from authors of Public Health England’s Immunisation Against Infectious Disease (the Green book).

Also of interest

Managing anaphylaxis in the COVID-19 vaccination setting

Advice on managing anaphylaxis in the vaccination setting with specific reference to COVID-19 vaccines.

Change history

  1. PEG and polysorbate 80 sections updated and editorial changes made.
  1. Addition of COVID-19 Vaccine Prior Allergy Decision Tool and made other editorial changes.
  1. Changed 'First dose of AstraZeneca COVID-19 vaccine or other medicines allergy' heading to 'First dose of AstraZeneca COVID-19 vaccine allergy'.
  2. Removed 'Individuals with a history of immediate onset-anaphylaxis to multiple classes of drugs or an unexplained anaphylaxis should not be vaccinated with the Pfizer-BioNTech COVID-19 vaccine, except on the advice of an allergy specialist. However, the AstraZeneca COVID-19 vaccine can be used as an alternative (if not otherwise contraindicated), particularly if they previously tolerated an injected influenza vaccine. The vaccine should be administered in a setting with full resuscitation facilities (e.g. a hospital), and a 30 minute observation period is recommended' from 'First dose of AstraZeneca COVID-19 vaccine allergy' section as it is also in the PEG section.
  1. Removed 'Patients with systemic allergic symptoms after the first dose of the Pfizer-BioNTech vaccine may be considered for a second dose using the AstraZeneca vaccine, and should be observed for 30 minutes following vaccination' from PEG section as this was from an older version of the Green Book.
  1. Removed the statement in the PEG 80 allergy section that although polysorbate 80 is quite similar in structure to PEG, there are no reports of PEG-allergic patients reacting to it (e.g. when receiving other vaccines), as the BSACI COVID-19 Vaccinations and Allergies FAQ no longer states this; updated the section with information from the Green Book on polysorbate 80 and flu vaccines.
  2. Link added to the UK Chemotherapy board Clinician Frequently Asked Questions (FAQs) and guidance on COVID-19 vaccine for patients receiving Systemic Anti-Cancer Therapy in 'other drugs' section.
  1. Information on prior allergy common to all vaccines moved the main page covering common allergy points.
  1. Added "Flowchart for managing patients who have allergic reactions to the first dose of COVID-19 vaccine" to "First dose of AstraZeneca COVID-19 vaccine or other medicines allergy" section; added a new section "Summary of allergy considerations", including a summary table.
  1. Updated to reflect changes in the Green Book: "Background" section updated; "First dose of AstraZeneca COVID-19 vaccine or other medicines allergy" section updated, including addition of BSACI management advice for people who had a reaction to the first dose of vaccine; added which patients should be discussed with an allergy specialist prior to vaccination in the "other drugs" section.
  1. Changes made to clarify advice in relation to allergies and excipients
  2. Changes made to include page as part of a series covering similar topics
  3. Changes made to clarify advice in relation to other allergy considerations, including addition of advice regarding latex
  1. Polysorbate 80 information added.
  1. PEG section modified, based on updated information from the Green Book.
  1. Removed the statement in the PEG allergy section that polysorbate 80 is found in many vaccines and there are no reports of PEG-allergic patients reacting to it e.g. when receiving other vaccines, as the the BSACI COVID-19 Vaccinations and Allergies FAQ no longer states this and updated with advice from the Green Book.
  1. Published